Composition of matter and process for preparing metal for painting



Patented Feb. 10', 1925- UNITED STATES PATENT OFFICE.

JAMES H. GRAVELL, or ELKINS PARK, PENNSYLVANIA.

COMPOSITION Oll MATTER AND PROQESS FOR PREPARING METAL FOB PAINTING.

Io Drawing. 7

To all whom it may concern:

Be it known that I, JAMES H. GRAVELL,

a citizen of the United States, residing at acid runs, soldering fluids and the like so that the metal may be properly prepared to receive a coating of paint, varnish or similar material. As material to which my invention relates-is usually applied by the hands, a further object of the inventionis to provide a material, whichwhen properly manipulated, is not harmful to the skin.

It has been the custom to use mixtures of phosphoric acid containing higher alcohols, such as butyl alcohol, but owing to the great oil solvent properties of those alcohols the natural oil of the skin is removed and the hands are no longer protected against the danger of chapping I have discovered that acetates of the lower alcohols, such as ethyl acetate, can be used to advantage in connection with mixtures containing metal etching acids to make them properly wet the surface to be cleaned and to avoid their unduly attacking the hands.

Since metal etching acids and ethyl acetate are not miscible, it is necessary to add alcohol and one of the lower alcohols (ethyl, methyl, or propyl) may be added in order to make them miscible. Water must also be added to bring the mixture to the proper commercial strength. However, an

admixture of ethyl acetate, alcohol, and water is not stable, but on standing a certain amount of acetic acid is formed at the expense of the ethyl acetate and water; therefore in order to stabilize the admixture I provide acetic acid which not only accomplishes that result but also assists the metal etching acid in cleaning the Work.

Application filed October 11, 1923. Serial No. 667,822.

By experiment I have discovered that it is necessary to have in a stabilized admixture of metal etching acid, Water and acetic acid at least 7 by volume of ethyl acetate and at least 30% by volume of alcohol in order to properly perform the work of causing the acidor acids to wet an oily surface. This can be accomplished by using commercial materials according to the following formula:

Formula N0. 1.

Gallons.

85% ortho phosphoric acid ;0.124 Alcohol (ethyl, methyl or propyl) .368 Ethyl acetate .082 80% acetic acid .068 Water .358

Owing to the presence of the acetic acid the above admixture is primarily stable.

It is possible to omit either the ethyl acetate or the acetic acid" by proportioning the other ingredients in such a way that when the admixture has by reaction and combination become stabilized, the missing ingredient will be formed and be present in the resulting stabilized admixture. For instance the following formula may be used which after standing becomes practically the same as formula No. 1.

l 'or'rrmlaa No. 2.

. Gallons. 85% ortho phosphoric acid 0.124= Alcohol .300 Ethyl acetate .150 Water .426

As a result of standing the ethyl acetate and the water decrease, acetic acid forms and the alcohol increases.

If desired the ethyl acetate may be replaced ,by acetic acid provided the remaining ingredients are properly proportioned as shown in Formula N 0. 3.

Gallons. 85% ortho phosphoric acid ..0.124. Alcohol .450 Acetic acid 80% .150 Water .276

In becoming stabilized or balanced, on

a painting, phosphoric acid is preferably present because it greatly assists in preventing the metal from rusting after the admixture has been used.

A very practical formula embodying the above suggested variation is:

Formula N0. 4. 85% ortho phosphoric acid "0.12 1 gal. Denatured alcohol .300 Ethyl acetate .150 Sodium acid sulphate .700 lbs. Water .396 gal.

According to my process the work just prior to painting is treated with a balanced alcohol-ethyl acetate-acetic acid-water admixture in the presence of a metal etching acid by spraying, dipping or brushing. If necessary, the action of the admixture may be assisted by an abrasive. When the metal has been sufliciently cleaned, the spent admixture is removed. This may be done by wiping, by blowing off for instance with air or steam, or by Washing with water. After the spent admixture has been completely removed and the surface has become dry, it is ready for painting.

From the foregoing description it appears that I have provided a composition of matter for cleaning metal surfaces in which the proportion of the ingredients is fixed and stable, and which can be at all times relied upon to contain at least the necessary minimum quantities of alcohol and acetate, and from the foregoing description it further appears that by providing ethyl acetate I can avoid such use of higher alcohols, for example, butyl alcohol, as might result in undue attacks upon the hands of the workmen.

I claim:

1.. A composition of matter for preparing metal for painting comprising an admixture of a metal etching acid and a stable solution containing alcohol, ethyl acetate and water.

2. A stable composition of matter for preparing metal for painting containing a metal etching acid and ethyl acetate.

3. A stable composition of matter for preparing metal for painting containing a metal etching acid, ethyl acetate and alcohol.

4. A stable composition of matter for preparing metal for painting containing a metal etching acid, ethyl acetate, alcohol and acetic acid.

5. A stable composition of matter for preparing metal for painting containing a metal etching acid, ethyl acetate, alcohol, acetic acid and water.

6. A stable composition of matter for preparing metal for painting containing a metal etching acid and at least 7% by Volume of ethyl acetate and at least 30% by volume of alcohol.

7. A stable composition of matter for preparing metal for painting containing phosphoric acid and ethyl acetate.

8. A stable composition of matter for preparing metal for painting containing phosphoric acid, ethyl acetate and alcohol.

9. A stable composition of matter for preparing metal for painting containing phosphoric acid, ethyl acetate, alcohol and water.

10. A stable composition of matter for preparing metal for painting containln phosphoric acid, ethyl acetate, alcoho, water and acetic acid.

11. A stable composition of matter for preparing metal for painting containing phosphoric acid, ethyl acetate, alcohol, water, acetic acid and a soluble acid sulphate.

12. A stable composition of matter for preparing metal for painting containing phosphoric acid, ethyl acetate, alcohol, water, acetic acid and sodium acid sulphate.

13. The method of preparing metal for painting consisting in treating it with a metal etching acid in the presence of a stabilized solution of ethyl acetate.

14. The method of preparing metal for painting consisting in treating it with phosphoric acid in the presence of a stabilized solution of ethyl acetate.

15. The method of preparing metal for painting consisting in treating it with phosphoric acid in the presence of a stabilized admixture of ethyl acetate, alcohol, water and acetic acid. 1

16. The method of preparing metal for painting consisting in treating it with phosphoric acid in the presence of a stabilized admixture of ethyl acetate, alcohol, water and acetic acid, removing the said acid and admixture and causing or permitting the metal to dry.

17. A composition of matter for preparing metal for painting comprising a stable fluid admixture of metal etching acid, water, a lower alcohol, ethyl-acetate, and acetic acid, the alcohol and ethyl-acetate content being primarily fixed by the presonce of acetic acid which opposes acetic acid, the alcohol and ethyl-acetate content acid-forming reaction between the alcohol being primarily fixed by the presence of and ethyl acetate. acetic acid which opposes acetic acidform- 18. A composition of matter for preparing reaction between the alcohol and ethyl ing metal for painting comprising a stable acetate.

fluid admixture of hosphoric acid, water, a

a lower alcohol, et yl-acetate, and acetic JAMES H. GRAVELL. 

